In general, during dialysis treatment, a blood circuit which extracorporeally circulates blood collected from a patient and returns the blood into an internal body of the patient is used. For example, the blood circuit is mainly configured to have an arterial blood circuit and a venous blood circuit which can be connected to a dialyzer (blood purification device) including a hollow fiber membrane. An arterial puncture needle and a venous puncture needle are attached to each distal end of the arterial blood circuit and the venous blood circuit. The respective needles are adapted to puncture the patient so as to perform extracorporeal circulation of the blood for the dialysis treatment.
Out of these, a peristaltic blood pump is arranged in the arterial blood circuit. In a state where the arterial puncture needle and the venous puncture needle puncture the patient, the blood pump is rotated. In this configuration, the blood collected from the internal body of the patient can be fed to the dialyzer side. Furthermore, an arterial air trap chamber and a venous air trap chamber are respectively connected to the arterial blood circuit and the venous blood circuit. The extracorporeally circulated blood is configured to return to the internal body of the patient after bubbles are removed.
Incidentally, in the related art, as disclosed in PTL 1, a configuration is adopted in which a priming solution supplying line for supplying a priming solution (physiological saline solution) during priming is connected via a T-shaped tube to an upstream side (that is, a side to which the arterial puncture needle is attached) from the blood pump in the arterial blood circuit, and in which the priming solution can flow into and can fill various configuration elements such as the blood circuits and the air trap chambers connected to the blood circuits during the priming prior to the dialysis treatment.
In particular, in the above-described blood purification apparatus in the related art, in order to automate the priming, an overflow line is extended from an upper portion of the venous air trap chamber, and a closed circuit is formed by connecting a distal end of the arterial blood circuit and a distal end of the venous blood circuit to each other during the priming. The priming solution supplied from the priming solution supplying line is circulated in the dosed circuit, and is discharged through the overflow line. In this manner, filling with priming solution can be performed automatically.